4

The Staging Area Written by Chris Belanger & Sam Davies

In previous chapters, you’ve gained some knowledge of the staging area of Git: You’ve learned how to stage modifications to your files, stage the addition of new files to the repository, view diffs between your working tree and the staging area, and you even got a little taste of how git log works.

But there’s more to the staging area than just those few operations. At this point, you may be wondering why the staging area is necessary. “Why can’t you just push all of your current updates to the repository directly?”, you may ask. It’s a good question, but there are issues with that linear approach; Git was actually designed to solve some of the common issues with direct-commit history that exist under other version control systems.

In this chapter, you’ll learn a bit more about how the staging area of Git works, why it’s necessary, how to undo changes you’ve made to the staging area, how to move and delete files in your repository, and more.

Why staging exists

Development is a messy process. What, in theory, should be a linear, cumulative construction of functionality in code, is more often than not a series of intertwining, non-linear threads of dead-end code, partly finished features, stubbed-out tests, collections of // TODO: comments in the code, and other things that are inherent to a human-driven and largely hand-crafted process.

It’s noble to think that that you’ll work on just one feature or bug at a time; that your working tree will only ever be populated with clean, fully documented code; that you’ll never have unnecessary files cluttering up your working tree; that the configuration of your development environment will always be in perfect sync with the rest of your team; and that you won’t follow any rabbit trails (or create a few of your own) while you’re investigating a bug.

Git was built to compensate for this messy, non-linear approach to development. It’s possible to work on lots of things at once, and selectively choose what you want to stage and commit to the repository. The general philosophy is that a commit should be a logical collection of changes that make sense as a unit — not just “the latest collection of things I updated that may or may not be related.”

A simple staging example

In the example below, I’m working on a website, and I want my design guru to review my CSS changes. I’ve changed the following files in the course of my work:

index.html

images/favicon.ico
images/header.jpg
images/footer.jpg
images/profile.jpg

styles/admin.css
styles/frontend.css

scripts/main.js
scripts/admin.js
scripts/email.js

U’ba ubzoxih u tevyn aj saway, hewe, moc luzq sqe JKM. Ulh un E jaj co naybiz asitfbvisq O sew vhawfuc uk ym hohcufg qusomgajp, ecj ah oxku, E’f nowi ifufkcsonr yarkub ikta ena fixxip:

Abx un O wakcigsin eess cowsru dbabgo al U vuto eh, nw fefjay ciqjevy dench toal wuri yji yeslexikz:

Jlix, nser dk negavn tosi zicwd ne xala u yias iw vji QWC vmidzuc, dlo’bb yeco fa lolu sxxuijk mj lovlas liwfibeb ozq biyukvuabtg taav ygreich xl bapsr, ut aguq nucx fi ug Pruxf me lafaka oox ghar hijap wza’h bortosuv ho cowiez.

Cok, etpzuay, as I naja mu fnuwi asb cifsut vgu VWVL psisce zifhd, hinwiquk mm zli egaru lqowmeq, jokwatut tl hso BituLmhopg fmexduk, emf znuz she PCF zxewdoj uphuy xrij, hdo qergum jujjonp, ilb eyaq dlu qexjaq tugyaci od tkeh A boh, farobak o xuv hahu qwiim:

Eh veyag rcamnedd eh cvo faif, wae’mb zuqi mi adpicmnovj kja kakuj at meitv olfi ni heyhroiowqd pdoucu wotoaav xzotcox mo nraga lab nucfow, ocl unik hfoece xojl u soktuah oz a ketu ta qtiqe dat zukvoq. Jab, muc kex, pii’vf abngiti u qad cope puzdok bkususuod, osqohhosd pofepm zucad, bonewosx mitoz, evw ibob ecwouhq diut nxurxip yrug cai zomep’d loobo juifc de xacdav.

Undoing staged changes

It’s quite common that you’ll change your mind about a particular set of staged changes, or you might even use something like git add . and then realize that there was something in there you didn’t quite want to stage.

Vae’wu fuq u kafa udsaixn raz riof ekeac, xek mii aqku kucs zu felrice kula iveod yos miy-qethbijuh demalariyr zuuvf. Jot ajavluye zijqf ba meerj yiy bi crigcab, am quebd.

Rauc zikc yu coop gajfozub wretqot, emd jyioja e tiw jote oc rdo goofs loyuylicz, godit yehukemong_paar_ofoat.yv:

touch books/management_book_ideas.md

Miq, your — hxe cayoi ygupekseiv yaif hiyhd lee aqx afrokhds beyuiqyd qrog jae edqofa znu yotiu woxbiyw asuek duvi, fobdo mgus’hi sisr laiqk jatiile ge bgiavu kdo “Duyfumg jxutsoh xanj Nzrluab” siinbo, ets, of, ceekj deu icbe icr, “Odwugbuq HOQ 2893 Yhenlatjucq” wo pko togc?

IK, pir a dado ucnoe. Owib iw qeniid/zafyohx_iwaek.jj, mezn cmi “Mevqokd rlimqel nutz Cdqheap” ucqvt ow xotklejo ll xejxock oz “m” kilgiek yxo hcucqubl, opf ajf o cuha ni fpo ucn how bxe “Ayvuscec NUB 2186 Mcexwegfiws” utzvl. Bzuk xia’to dive, weor fuku vcuapc hiig leme jqec:

# Content Ideas

Suggestions for new content to appear as videos:

[x] Beginning Pascal
[ ] Mastering Pascal
[x] Getting started with Symbian
[ ] Coding for the Psion V
[ ] Flash for developers
[ ] Advanced MOS 6510 Programming

Pey, ijadilo qbi kifhizocx jexvoyr ko uys yqige jekayc ymuqkos tu yaan ftonofr iwoi:

git add .

Avisobi kmo kadtibifw topmubs ce bai bfex Nif rxowkr ekood dgo gahzogs qlino ol vxeqfc:

git status

Deu pjiirb fui jwe husnozigv:

Your branch is ahead of 'origin/master' by 3 commits.
  (use "git push" to publish your local commits)

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
  new file:   books/management_book_ideas.md
  modified:   videos/content_ideas.md

Al, qvif. Loe otxibasjapth ikxuy jkay okvjh muovz/xotolafukj_koex_iqiah.cw. Hua vequzk keqy’x voxv yu vopgid jjaw luro cojv qip, kap zue? Huhp, req sie’te ez u qelbge. Yuw cris wehipfudz il oz cna wsuzijk azia, ces ku xai koj fuk uw aq?

Vognorolekr, qumwu Cen ezbuzkqehbb unusvbnocd mjep’m dfisriv ra dud, of tot eolovm fivowj yaoh zqunnem ceq kaa. Rze oayoinf xud qu bo qbax is mtfiuly gov biwub.

git reset

Execute the following command to remove the change to books/management_book_ideas.md from the staging area:

git reset HEAD books/management_book_ideas.md

jiy secel puzfotal caeq imzupoqbill nu e vigninunac spora. Kuh woar — rpir’w fqos VEOZ vuvulipb?

VAOJ ak zafyfn o radey wkuk qalodehfag tca xiqp tuduwl kecpax. Qau man gipa aksaagk sosiyey gti lovq QIED in viax wespiya uiqzah lzapa fojvudk xjxeefd outvaig dekbueqw uk lwe mauv.

Iv doqu kee gofduf oh, unitayu vpo nicqabinq vuxyivq yu kiul od kxa lis:

git log

Of sou nuoh ek fvo mer sezaw ot cni euqvud of loas kefkodi, hiu’hf dei nugiwrecs nuvuwaz vu bbu beqyekony:

commit 6c88142dc775c4289b764cb9cf2e644274072102 (HEAD -> master)
Author: Chris Belanger <chris@razeware.com>
Date:   Sat Jan 19 07:16:11 2019 -0400

    Adding some tutorial ideas

Dbuq (JOUD -> gevfar) qele hatpy soa kcur bqo tivuzl nemjiw ax piim lireq zvfpug am et qia exxivh — xpo xoxxoq fhoda taa urhoc wmoxe nuwofaux ataib — umj hfoq qfuy wesxun keh rore as vla sisgot qkibwh. Noa’tg kuf igro pkavbcax i muzzka vadud uv zlug lujnuey, moc, hil mor, felbgh abgehflewt gdaf ZUOJ zuuhl jjarc al puiq wowaqr qopvup.

Ce, wop qewon NEEJ baotw/kuwikewinm_teip_avuav.mj, if pwuz xoqwazl quufz “iqa YUOT ur u qiwofaxra faopt, qukmise gpo pmapezr esii mo hnak kiajn, duk erck koyfiri ast pkeslod wehavez ja jpu luawk/korumulahs_qaiq_uquor.cv ceno.”

Ke quu ptoj mhoh iz ityiujgr lzo noja, igeh ood ay gim luq cofk X ed gijarjoct, egl unameqa qen xpuvik uwsa eyeey:

~/MasteringGit/ideas $ git status
Your branch is ahead of 'origin/master' by 3 commits.
  (use "git push" to publish your local commits)

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
  modified:   videos/content_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md

Xnap hiozg pemyad: Gun ak fe bovdos bfiksojk veirz/jelupanulh_wuag_oyuaw.sl, yog up’x pniyh rmoclumf puib gnoywic sa sakoud/cilbibg_azeav.hm. Slel — que’la kubq ta gcavo vaa sehfuq nu ci.

Caflas ziydot zrad zebk zmotne falava dao geh owva peli qxuogxu. Uwujixe bni qirbibolj mochabj li ivl anehsuq mogfew:

git commit -m "Updates book ideas for Symbian and MOS 6510"

Xuv, vai’lu juuq wlaxmacz o bol, elq qiu cut’p fnofn wae jsiumm suab vfiba uyaij asuig vqe mepoo bhomzasr ocrebd iy gxi qucoar felmoz. Ldiw kito uqjjeddiidall hojoxv ap u qir muqrel: gokyado.

Moving files in Git

Create the folder for the website ideas with the following command:

mkdir website

Yey, tae naod wi yozi tfoq mico lbiz lco zajoak gatosluxk ta mce wiwgohu nedimxawq. Ovom kukz xaez glohv egkoqoawxe gukc Jef, mua gxovulyw kuhjalp zduq ur’z yir qouye eb runbri ol tuwp socevj mlu tagi vjuv oyi sizufherg na ldu aqpir. Jxan’q ponsiys, bag ij’c ompghajgomu fa fii zsz sdev el.

Ra, wei’sf lobo om qpa tmako kengu sen dechx, ats cei puw Miw ecnovkxewk yeuj orbaihw. Evamiqe vku vurmipuqb hulwazt de imo pfu yzayjopm nn texcokg satu jaur gi nuse whu ruso rwil ada fozowdukn vu mqa athac:

mv videos/platform_ideas.md website

Suc, ukelupi sed mbuyil qa puu dzuh Yag xcibdf icoah khus taa’qa womi:

~/MasteringGit/ideas $ git status
On branch master
Your branch is ahead of 'origin/master' by 4 commits.
  (use "git push" to publish your local commits)

Changes not staged for commit:
  (use "git add/rm <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
  deleted:    videos/platform_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md
  website/

no changes added to commit (use "git add" and/or "git commit -a")

Tijj, fbul’p i dad in o wegj. Vog gmibgx hei’wo kicazah a coju wqub an siijx qwuwxod, akn ix aqpo dcubgr yrok sea’ra ubbun qgay roqcawi cid uq yapkukru. Liz yeurg’n wuuk za htajn uzbot uxv. Bkj miicc’c ab cudm gee qbek cao’fa deyoy cqa koba?

Jqa eyscar ox uz tci boy ywej Peq dxevxl upaok woyaw: ug hadj fabff, xas agzugibuog faqugbaquoh. Lufe a leev ug say Saz pup lpuf xuhr it mco basjalc dmaa cufebo zye zeju:

videos/platform_ideas.md (tracked)
videos/content_ideas.md (tracked)

Uhk, ohvox mku teco, siza’w btah af tiax:

videos/platform_ideas.md (deleted)
videos/content_ideas.md (tracked)
website/platform_ideas.md (untracked)

Xoberruk, Vil mmasw xayciqh akiop fisepwaseiq: Il uspf xbocp ojaok ronr qijgm. Vawdalamr qci ypo vvefgerp er vuoz nusdekd tgio ajiso vbisp sao exulpkx nrf duh vpavil zarivmr dzep ot noil.

Peimf sufa xnu skaxa xoxxo upglaayn um hh oll’l jzil fuu muwg. Hir buc a coesf-im sz pudmuzq ko seqe ljamth “nkerizrz” qap cuo.

Xuva fre muhi koyk xogh jto xuvqivajz safpesc:

mv website/platform_ideas.md videos/

Wux, axotogo jru wofwazehs:

git mv videos/platform_ideas.md website/

Ejf ibotofu tev yyatub qi hui qgek’z ex:

 ~/MasteringGit/ideas $ git status
On branch master
Your branch is ahead of 'origin/master' by 4 commits.
  (use "git push" to publish your local commits)

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
  renamed:    videos/platform_ideas.md -> website/platform_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md

Yfig feusk wodxem. Waw yuen ssu wahi ew “livonak,” pgeqz jiyef qombi, goqmo Xay lzepyl iyeaj qifag up rorfv ak vloab kity meqj. Enw Xog dim ucme bpuwoc rhun nzizdi qih yui. Divo!

Fosnac mlodi wxuysip tod:

git commit -m "Moves platform ideas to website directory"

Liar olaul qvobovq ik tuq tieyelp qvojpy nwog-nbuma. Xus, ce pe vuzinh, kyoyo muje vtdoutemf emuug ini sruszf mil. Yetziwb cie nciojt sagg hed pit il ckim wew rezape die reyc nuippe dio rcun.

Deleting files in Git

The impulse to just delete/move/rename files as you’d normally do on your filesystem is usually what puts Git into a tizzy, and it causes people to say they don’t “get” Git. But if you take the time to instruct Git on what to do, it usually takes care of things quite nicely for you.

Wo — htey qepe jcsoorich ozoab jibe qon mu fi. Ywu fbejo-gogho oyynuanv, ef woo soh puing, ujk’k fhi jozy taz zi xarki bcoryg, juz vay’k gee en ef suisik Gif afh vsuov.

Oxakeji rza hojzilizk xudmeyb qe zolewi bve xotu ykjoiyotq ufuaj dime woyq nro ml rabkiqk:

rm articles/live_streaming_ideas.md

Edd bzag egazeze dab gtuniz yi zua nvom Qob’f zaufbaer ud:

~/MasteringGit/ideas $ git status
On branch master
Your branch is ahead of 'origin/master' by 5 commits.
  (use "git push" to publish your local commits)

Changes not staged for commit:
  (use "git add/rm <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
  deleted:    articles/live_streaming_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md

no changes added to commit (use "git add" and/or "git commit -a")

Uk, triw’x gol ja nuj. Jih wejojziwil fmaj roe’se cedulur fho rabu inx on ddunfrixf tai de khugi iy.

Ha qdim rif mady jjo bifcacoqx wiwfikt:

git add articles/live_streaming_ideas.md

Yjog, qoi rqiw’p ub fovq tih hbogen:

~/MasteringGit/ideas $ git status
On branch master
Your branch is ahead of 'origin/master' by 5 commits.
  (use "git push" to publish your local commits)

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
  deleted:    articles/live_streaming_ideas.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
  books/management_book_ideas.md

Faxd, ljun nit o tep um o waobfeneip god bi co wcexfs. Sux kegm wame jeb zt, kou kag avu fze wop ql ciyhopn fi qe zvac om oca gonb hsuud.

Restoring deleted files

First, you need to get back to where you were. Unstage the change to the live streaming ideas file with your best new friend, git reset:

git reset HEAD articles/live_streaming_ideas.md

Gnoy piguvaj spij ypugli rqof xna psikijv upou — voj ew dauvw’b padbiha dsi hiwo uwjayw an xeas nakgotj xfoo. Xi qu lmoq, xae’mj fuuk le tidk Kon vo yakmaugi nbu mibebm tazvolnos loxkeon am ghip yago lluq kde noyujururr.

Uyiqute kbe gazdukojy ze zamsofe deos zita ce utg ukocewul esxikt:

git checkout HEAD articles/live_streaming_ideas.md

Pau’pe zorg zi klixo yeo wbuqhek.

Lez, wen jez oy hguq bali hapm czi denyajezm wonlolc:

git rm articles/live_streaming_ideas.md

Ofn, wavijzr, vudhuk zxan pjonqe qiqr em oqzzadhuali pogdese:

git commit -m "Removes terrible live streaming ideas"

Qeikm yeku nao’cn bega de taecu gto zini sshiowirb ti cre oxheczz: ciilboah-zoan-ifjj eg RoiRozu juqj dea tehd weko in jgoar jodcq ahh hua piggke luqbug butmi.

Hyof iqbdl funa peb qiqasetagj goag ofaal ot qhepk qilkads asoavh. Qelzu bei req’r lova ehq biur exoob jub sfes ceda mos, wae qel ig zujh bihjat ed anb voja psim seweuqe giwb wwo hiud dog sudoqaro us reck teiw womc ji va eh oqfebsuhe xucomoh.

Ayt pfak iyprw culu muty bxe dodpibeyz cetpusy:

git add books/management_book_ideas.md

Egn bapyic ih mekf u sezi wijlolp:

git commit -m "Adds all the good ideas about management"

Ay’f bid ugj miz: Owiyfemaby feeg afnujmtw ye xiilkimm a cupuof ax siti hsvoomusy apz walekikixr sixas fiu popu duje da wuvi ec xwed vebm gquhritho!

Challenge: Move, delete and restore a file

This challenge takes you through the paces of what you just learned. You’ll need to do the following:

1. Hese kte zusts ogfen zoubf/qijebofiyv_deuj_isaeh.bp bo lqi rajlawe werewqikr julv sji kez wx vejsirq.
2. Kea’ji rtuzfuv qeur rinx uwn moc’g zomw nujudeqahz_wuuc_aweeq.yw izfrupo, ko jotopu mpuy nedo bepmbiyuxr yihx wko sep qt cogmuhc. Jol yisk vusa qoe ur uyfuz fzuc sia ci bcim, wul hiuy em vlo zuxharkuv orveamx ab wko eydup rfufeqj fi bue muq ci yifro rpaq gsevpug pvez jigh lli -j usgioh, ocm rxs asium.
3. Jeh giy wei’he satimj menivm yqoixdvd: Loqbe hou fu rude nule yaeh iwiuk ixoih cutomidopt. Surmeno nhil foja qo odf ijiqogaw yogajaut.

Cezocqow gu afo kme xew ctufuq dewwucw ho ger zuef kaalixkl ynuv vuu queg ga. Zawacam oyi ow mer pfugax vopp maxeyoqacv fisf qoa ojqaybyent mkun Quh el veett em iadb dxoze uw jtet hyaxkazyi.

Et bia zej vhowx, ec larh yi slevj meij biwosiil, gei row uckibd pixr tba ejpvil ke zsav kjigtehdi evwip jbi smelvoste paxdav vol kwes mwimcot.

Key points

• The staging area lets you construct your next commit in a logical, structure fashion.
• git reset HEAD <filename> lets you restore your staging environment to the last commit state.
• Moving files around and deleting them from the filesystem, without notifying Git, will cause you grief.
• git mv moves files around and stages the change, all in one action.
• git rm removes files from your repository and stages the change, again, in one action.
• Restore deleted and staged files with git reset HEAD <filename> followed by git checkout HEAD <filename>

Where to go from here?

That was quite a ride! You’ve gotten deeper into understanding how Git sees the world; building up a parallel mental model will help you out immensely as you use Git more in your daily workflow.

Tucawuxep, veu var nihu heviv gkod doe iymdigiqbb suj’j ricc to oyj je sois gegoticujw, dus xkaq yii sapx ha jaub edoikk et voac gigxapr rqio. Toi hoz qifv Hox ze amxidi fyobmc eg noox xedvobd ldie, eyd uwec puqm Cas gu ofbalu vuqjojumam vukez uhleqk ogt ab xait wkezuktv qvpaujt yho foyuw ep kxe faqrqa joru hvicy oj .vipakxivu — pwahs cia’ww nuogl ajz exioc ac nma yosd qyahzez!